Bag construction

ABSTRACT

A packaging system using side by side connected tunnel-top bags, or alternately, bags having spreadable flaps at their tops. The closure sealing characteristics of such bags is improved by permitting the bags to be substantially free of each other at their lower regions but securely connected together adjacent upper regions thereof. Upon filling, the free or mid-portion of the bag sides distort inwardly since material is pulled from the sides to &#39;&#39;&#39;&#39;bloom out&#39;&#39;&#39;&#39; the bag. The sides at upper regions, however, being connected as indicated, resist pull or movement inwardly, thereby causing a tautness in the upper parts of the bag material. A substantially wrinkle-free region is thus obtained for a closure seal.

United States "Patent [191 Titchenal et al.

' [4 1 Feb. 12, 1974 [54] BAG CONSTRUCTION [75] Inventors: Oliver R. Titchenal, Avon; William A. Armstrong, New London, both 91 Ohio Y 1 [73] Assignee: Basic Packaging Systems, Inc., Avon Lake, Ohio 22 Filed: Nov. 15, 1971 21 App]. No.: 199,068

Related U.S. Application Data [63] Continuation of Ser, No. 838,992, July 3, 1969,

abandoned.

52 U.S. Cl. 229/69 [51] Int. Cl B6511 27/10 [58] Field of Search... 206/57 A; 150/1; 229/53, 69

[56] References Cited UNITED STATES PATENTS 3,033,257 5/1962 Weber 150/1 2,993,313 7/1961 Hogan Primary Examiner-D0nald F. Norton Attorney, Agent, or Firm-Gustalo Nunez [5 7] ABSTRACT A packaging system using side by side connected tunnel-top bags, or alternately, bags having spreadable flaps at their tops. The closure sealing characteristics of such bags is improved by permitting the bags to be substantially free of each other at their lower regions but securely connected together adjacent upper regions thereof. Upon filling, the free or mid-portion of the bag sides distort inwardly since material is pulled from the sides to bloom out the bag. The sides at upper regions, however, being connected as indicated, resist pull or movement inwardly, thereby causing a tautness in the upper parts of the bag material. A substantially wrinkle-free region is thus obtained for a closure seal.

16 Claims,- 10 Drawing Figures BAG CONSTRUCTION This is a continuation, of application Ser. No. 838,992 filed July 3, 1969, now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to bag constructions and, more particularly, to bag constructions wherein distortion of the bag accompanying filling is controlled to provide a wrinkle-free region for placement of a closure seal.

2. Discussion of the Prior Art Known to the prior art are chain or connected together bag put-ups or stock adapted to permit continuous bag feeding to filling and sealing machinery. Such bags are normally of the tunnel-top variety, or alternately, include speadable flaps associated with their top ends.

Tunnel-top bags, for example, are mounted in filling machinery in a manner more or less analogous to a curtain-and-rod mounting arrangement (see my copending US. Pat. application Ser. No. 727,464, filed May 8, 1968 now US. Pat. 3,559,894). Mounting in this manner contributes, among other things, to controlled feeding of the bags. Prior to filling, of course, the tunnel-top is cut apart to open the bag. tops such that a product fill can be gravity dropped or otherwise inserted into each bag.

Bags of the type having spreadable flaps are similary acted upon by such machinery except, as is understandable, other arrangements are employed for initially mounting the bags in the machinery.

In any event, the bags as they approach the sealer, i.e., after filling, are oftentime badly distorted by product fill. The present invention is concerned with smoothing out a region of such bags suitable for placement of the closure seal.

Accordingly, it is among the objects of the present invention to provide the following:

A bag constructed so as to minimize distortion or wrinkling at its top end accompanying filling of the bag, whereby a smooth or generally wrinkle-free region is provided for placement of the closure seal;

Aplurality of bags connected together side by side in a Siamese like connection to permit continuous feeding of the same to filling and sealing machinery and wherein the bags, subsequent to filling, present a substantially non-distorted area in the vicinity of their tops to assist in the obtaining of an air-tight closure of the bag; and

Chain bag constructions of a variety designed to split apart or separate from each other along certain lines of weakness following filling and sealing of the same, and wherein such lines of weakness are of sufficient integrity to hold in strategic areas accompanying filling such that a tautness is caused in the material at the upper re-. gions of the bag, and to a degree beneficial to sealing operations.

SUMMARY OF THE INVENTION Briefly then, the present invention contemplates improved chain bag constructions wherein distortion of the bag upon filling is limited to the lower regions of the bag. The upper regions or bag tops remain substantially wrinkle free to assist in obtaining an air-tight closure of the bag. Specifically, such distortioncontrol is accomplished by strategic connection between the bags whereby a tautness in the aforesaid upper regions is caused accompanying filling of the bag and of a degree sufficient to smooth out such upper regions.

The preferred embodiments of the invention are shown in the accompanying drawings, in which wheresoever possible, like characters of reference designate corresponding material and parts throughout the several views thereof in which:

FIG. I is a side view of achain of connected bag elements constructed according to the principles of the present invention; 1

FIG. 2 is a cross-sectional view of the connected bag elements of FIG. 1 taken along reference line 2-2 thereof;

FIG. 3 is a view like FIG. 1, only showing a modified form of the chain bag construction of the present invention;

FIG. 4 is a cross-sectional view of the bag elements of FIG. 3 taken along reference line 4-4 thereof;

FIG. 5 is a view like FIG. 1, only showing still another modified form of the chain bag construction of the seals certain of the chain bag constructions as contemplated herein; and

FIG. is a top view of the apparatus-of FIG. 9.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now more particularly to the. drawings, there is shown in FIGS. 1 and'2 a chain of connected bag elements 10, each including bottom and top ends 12 and 14 and two sides 16 and 18, respectively. Sides l6 and 18 are closed except at their uppermost extents or their upper regions 20 and 22, respectfully. Areas 23 and 25 reside beneath regions 20 and 22, respectfully, and comprise the closed upper portions of sides 16 and 18, respectfully. 1

Referring now specifically to FIG. 2, further structure of bag elements 10 includes front and rear walls 24 and 26 closed along bottom ends 12 by a fold 28; and

a strip of material 30 which extends along top ends 114 of bag elements 10, respectfully. Strip 30 is joined together along its opposite edges 31 and 33 with walls 24 and 26, respectively, such. as to form a tunnel or loop structure 32.

Such bag structure as described heretofore can be obtained by cross-sealing a length of tubular film or material at regularly spaced intervals thereon as denoted in FIG. l by strip seals 34; and by terminating seals 44 at a spaced distance from top ends 14 to leave the indicated open regions 20 and 22, as explained in more detail in the aforesaid co-pending application.

Referring again to FIG. 1, further bag structure includes lines of weakness 36 which extend between the sides 16 and 18 of adjacent or successive bag elements in chain 10, i.e., along the mid-region'of seals 34 and upwardly therefrom into the vicinity of tunnel 32.

Lines of weakness 36 at their lower extents comprise at least one slit or cut and preferably two slits 38 and 40 interrupted or separated by a land or joined region 42. The upper extremity 46 of each slit 40 terminates at a point below the upper end 44 of seams 34, respectfully.

The region comprising the area between extremity 46 and end 44, and the adjacent sides 16 and 18 of successive bag elements in chain 10, thisregion being hereinafter designated as material 48, is a region of criticalness to the connection between successive bag elements in chain 10, as will become more evident hereinafter.

At material 48 the strength of the connection between successive bag elements is preferably lessened somewhat by line of weakness 42 which is extended therethrough such as by means of perforations or serations 50, but not to the degree of weakening provided in lower'bag regions as represented by slits 38 and 40.

Referring now to FIGS. 9 and 10, there is shown machinery or apparatus 56 of a construction suitable for use in continuous filling and sealing of bag elements 10 of the type formed of heat sealable film.

Apparatus 56 at its infeed section 58 supports a device 60 on fittings or mounts 62 and 64, respectively,

, the device 60 being adapted for controllably feeding bag elements 10 to apparatus 56 in a manner to be described.

Device 60 basically includes a generally horizontally disposed first or top bar 66, and a second or diagonal bar 68 extending generally downwardly and inwardly from adjacent the forwardmost end 70 of top bar 66. As best seen in FIG. 9, bars 66 and 68 open angularly toward machinery 56 and are normally angularly paces 39 1 sasbn a n an e. apfapp pxim y 45. Support structure for device 62 comprises a horizontally disposed first support bar 74 depending rearwardly from forwardmost end 70 of top bar-66, and a cross bar 76 connecting together bars 66 and 74 adjacent mounts 62 and 64, respectfully. A second support bar 78 is connected to lower end 80 of diagonal bar68 and extends upwardly and Jfwardly therefrom to connect with cross bar 76 adjacent mount 62.

xrrsreaa'aasafi 3 8T apparatus 12 additionally includes a horizontally mounted mandrel 84 which is connected by means of an arm 86 to a hopper or fill mechanism 88. Mandrel 84 at its top edge 90 carries a 'cutting means 'or blade 92.

Thereafter, belts 94 and 96 continue rearwardly to re- 1 turn by means of pulleys 116 and 118. Located between pulleys 116 and 118 and hopper 88 is a sealing station 120 comprised of, for example, opposed heat sealing bars 122 and 124.

Machinery 56 can also include a conventional conveyer system or means to support bottom ends 12 of bag elements 10 throughbag filling the sealing (not shown), as for example, when filling with heavy products or when otherwise deemed desirable. I

In operation, connected bag elements 10 are normally delivered to machinery 56 in a cardboard or like shipping container 126. Container 126, including bag elements stored therein in a folded pile, is placed 'beneath the device 60 and the top portion of the container cut away. The bags 10 are then fed upwardly from container to around top bar 66, and thereafter directed downwardly to and underneath and around diagonal bar 68. From diagonal bar 68 bags 10 are delivered to mandrel 84 which mounts the same in a curtainand-rod like fashion through tunnels 32. The bag tops 14 are then gripped or squeezed between belts 94 and 96, and bags 10 directed to hopper 88 via knife 92. Knife 92 longitudinally parts tunnels 32 such that fill openings 128 form between the two parted edges or flaps 130 and 132 of the tunnel and sides 16 and 18 of each bag. Thereafter, edges 130 and 132 are plowed open by the leading or forward part 134 of hopper 88 and a product fill 136 dropped from the hopper through fill openings 128. The bags are then directed to bars 120 and 122 and a closure seal formed across their tops- 14 as is indicated at 138.

beneath hopper 88 and receiving fill 128 is designated as bag element A and those directly forward of A, bag elementsB, C, D, and so on.

Referring now to bag element A, the same as it receives product fill 136 normally tends to bow or otherwise move or distort inwardly along its sides 16 and 18, respectfully, i.e., material is pulled from sides 16 and 18 to accommodate blooming out the middle portion of the bag as it fills with product 136. Such side movement is readily permitted by means of slits 38 and 40 usually accompanied by breaking of lands 42. At the upper regions of bag 10, material 48, even though weakened to a degree by perforations 50, is provided with sufficient structural integrity or strength to resist being broken apart by product weight, i.e., the weight or partial weight of product fill 136 pulling on sides 16 and 18. Thus, a connection between the bags 10 is maintained for a distance below terminating ends 44 of seams 34 subsequent to filling and by means of material 48.

It has been discovered that by maintaining the connection at material 48 subsequent to filling, distortion at top ends 14 of filled bags 10 can be eliminated or minimized to assist in attaining an airtight closure seal 138.

Such discovery can oftentimes be visably detected by taut lines forming in the bag material. Such taut lines are denoted at 140 for bags B and C and as shown, reside generally in the horizontal direction. At bag A taut lines may or may not appear and if visible, will usually be angled somewhat with the horizontal due to lack of pull caused by unfilled bags 10 on the rearward side of hopper 88.

In any event, by means of such tautness, bags B, C, and D as they approach sealing station 102 present a substantially distortion or wrinkle-free area 142 suitable for placement of closure seal 138.

Moreover, the provision of perforation 50 in material 48 permits the bags 10 to be conveniently separated or split apart from each other following the filling and sealing of the same (not shown). Such separation can include the trimming of edges 130 and 132 from bags- 10, or the same can remain attached to serve as carrying handles for the bags. In the latter instance, for example, perforations 50 would preferrably extend through edges 130 and 132 to assist separation of the bags in the edge region. Where the flaps are trimmed, of course, perforations 50 need only extend to the region of closure seal 138.

A modified form of the present invention is shown in FIGS. 3 and 4 as embodied in a chain of bag elements 10a. Bag elements 10a are of similar construction to those depicted in FIGS. 1 and 2 except that the tunnel part of the bag has been slit or pre-slit to leave spreadable flaps 146 and 148 associated with the bag walls 24a and 26a, respectfully. Such bags can be formed from tunnel-top bags generally as described above, and by pre-slitting or cutting the tunnel part thereof, or alternately, can be formed more directly such as by folding and sealing web-stock material.

Certain further modifications to bag elements 10a include a conventional gusset structure 150 at bottom end 12a; and the use of dual or parallel seals 154 and 156 forming the adjacent sides 16a and 18a, respectfully, of successive or adjacent bag elements in chain 10a I A somewhat modified line of weakness 42a is also employed comprising at its lower part perforations 158 separated by narrow lands 160. Lines of weakness 42a in its upper region or region of material 48a, comprises perforations 162 separated by somewhat-wider lands 164. Thus, at its lower regions, line of weakness 42a is designed to break apart or split accompanying filling as indicated hereinbefore, and accomplishes this through extensive perforating in these regions, i.e., lands 160 do not provide sufficient structural integrity to hold when product fill is dumped into bags 10a. n the same basis, wider lands 164 or other suitable means (not shown) can be provided such that the connection at material 48 is maintained at least prior to scaling the bags closed whereby bags 10a will exhibit improved sealing characteristics of the type as indicated above.

Still another modified form of the present invention is shownin FIGS. -8 wherein bags b are put-up on a separate strip of material 30b such that the strip forms tunnel structure 32b. Specifically, strip 30b is folded longitudinally and joined along its opposite edges 31b and 33b to walls 24b and 26b, respectfully, at top end 14b, as is best shown in FIG. '7. Put-up by means of a strip 30b permits the use of side gusseted bags 10b, i.e., bags having conventional side gusset structure 166 and 168 along their opposite sides 16b and 18b, respectfully, (see FIG. 6).

Alternately, strip 30b can be secured to walls 24b and 26b only at strategic areas as denoted by seals or seams 170 and 172, respectfully. At seams 170 and 172 the four plies numbered evenly I'M-180, respectively, and comprising the gussetedregions of bag 10b, and the two plies comprising edges 31b and 33b of strip 30b are preferrably joined together as a single piece (see FIG. 8). Such construction prevents the gussets 166 and 168 from unfolding as the bags fill with product such that the gussets need not be refolded for closure sealing purposes. v

Bag elements 10b are filled by slitting tunnel 32b such as by the means described above. The closure seal (not shown) for bags 10b can extend, for example, in line between the inner extremities 182 and 184 of seals 170 and 172, respectfully.

Material 48b comprises the part of strip 30b between adjacent bag elements 10b as defined in the region below the closed upper portions 188 and 190 of sides 16b and 18b, respectfully. Thus by means of the provision of material 48b, bag 10b will-befound to include improved sealing characteristics of the nature hereinbefore disclosed.

A wide variety of materials are applicable for use in constructing bag elements 10b. For example, paper, burlap, cotton, synthetics such as nylon, as well as polymeric films such as polyethylene can be used. Such bag materials, except polymeric heat sealable films, are normally sealed such as at bottom ends 1212 by hotmelted adhesives for paper, or by sewing or stitching for paper or for any of the above mentioned fabrics such as burlap or cotton. Thus, bottom ends 12b of bag elements 10b can be closed such as by a seal 186 which can represent either a stitched seam or sealing such as by means of a hot-melt or other appropriate adhesive substance. Likewise, seals 170 and 172 can comprise stitching or seals formed by hot-melt adhesives or the like.

While certain representative embodiments and details have been shown for the purpose of illustrating the invention, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention. For example, the principles and teachings of the present invention are broadly applicable in instances where either a neat appearing or air-tight closure seal is required or is otherwise desired, on an efficient basis, for packaging systemsemploying chain bag stock.

Accordingly what is claimed is:

l. in bag elements each generally including bottom and top ends and two sides substantially closed except at their uppermost extents, respectively, and means connecting together the bags in side by side adjacent fashion to form a chain of bag elements, the improvement which comprises: certain of said means being located' at least in a vicinity between the closed upper portions of the adjacent sides, respectively, of successive bag elements-in said chain and terminating at a spaced predetermined distance from said bottom ends, said means having sufficient structural integrity to maintain a connection in said vicinity when subjected to a force as would be placed thereon when filling said bag elements successively, and those means located away from said vicinity being of-insufficientstructural integrity to maintain a connection when subjected to said force.

2. The bag elements of claim 1 wherein said bag elements are formed from a continuous length of plastic film or sheet, and are defined by cross-seals at spaced intervals on said length of plastic, said means connecting successive bags comprising a plurality of lands having predetermined lengths and predetermined spacing from each other such that the connections made in said vicinity have a structural integrity greater than those connections located away from said vicinity.

3. The bag elements of claim 2 wherein said lands are positioned in an area defined by said cross-seals.

4. The bag elements of claim 2 wherein said means comprises at least a singular land located at a predetermined distance t'rom said vicinity.

5. The bag elements of claim 4 wherein said means define a line of weakness located within said cross-seals thereby resulting in a separation of said bags from each other after the filling thereof and said separation resulting in the development of taut lines across the upper portions of the two sides of said bags thereby providing a substantially wrinkle-free area suitable for placement of a closure seal.

6. The bag elements of claim 5 wherein said line of weakness comprises a plurality of perforations of predetermined sizes. such that said cross-seals increase in strength when extended to a point upwardly towards said closed upper portions of said adjacent sides.

7. A chain of bag elements each including front and rear walls and two sides substantially closed, respectively, except ata region adjacent the upper ends of said bag elements, the bags being arranged in said chain in generally side-by-side fashion; and a strip of connecting material joined along its opposite edges to said front and rear walls, respectively, to form a continuous tunnel at the upper end of each bag element, means connecting together successive bag elements in said chain at a region between the upper closed portions of their adjacent sides, respectively, said means terminating at a predetermined distance from the lower ends of said bag elements and said connecting material located generally towards the upper end of said bag elements-having sufficient structural integrity to maintain a connec tion between said bags when subjected to the degree of force as would be placed thereon when filling the bags, and said means located generally towards the lower end of said adjacent sides having insufficient structural integrity to maintain a connection when subjected to 'said force thereby resulting in the separation of the lower portion of said bag elements from each other upon the filling of said bags.

8. The bag elements of claim 7 wherein said means comprises at least one portion of connecting material thereby defining at least one slit separating said adjacent bags, and defining a line of weakness permitting the lower portions of said bag elements to separate from each other subsequent to the filling thereof.

9. The bag elements of claim 7 wherein said strip of connecting material is adapted to be severed prior to the filling thereof, therefore to thereby provide freely speadable flaps associated with said front and rear walls, respectively.

10. In a chain of side-by-side connected bag elements of a type formed from a continuous length of plastic web material and including closing means for closing the sides of the bag elements from a region adjacent the bottom ends thereof to a region adjacent the top ends of the bags, the improvement of which, comprises, a line of separation defined between said side closing means of adjacent bag elements in said chain, said line of separation comprising a first region located at a point spaced downwardly from the upper terminating ends of said closing means and extending toward said bottom ends, said first region providing at most only a connection between said bag elements of a degree permitting the bags to bloom apart from each other when sub- 7 jected to the degree of force as would be placed thereon when filling said bag elements successively, a second region of said line of separation being located in a vicinity intermediate of said upper terminating ends and said first region, said second region providing a connection between said adjacent bag elements of a character adapted to remain substantially intact when subjected to the degree of force as would be placed thereon when filling said bag elements sucessively whereby said filling is accompanied by a tautness forming in the upper extents of said bag elements thereby providing a substantially wrinkle-free area suitable for the placement of a closure seal, said second region further providing a connection between said adjacent bag elements of a character permitting said bag elements to completely separate upon placement of said closure seal.

11. A bag structure comprising opposed continuous panels and seams located at spaced intervals thereon to compartment said panels into a plurality of linearly connected bag elements, the bottom region of said bag elements being defined adjacent and along one longitudinally extending edge portion of said panels, means closing said bottom ends, the top end regions of said bag elements being located adjacent and along the opposite longitudinally extending edge portion of the panels, said seams extending from adjacent said bottom ends toward said opposite edge portion and terminating in spaced relationship therewith, a siamese-like con nection located between adjacent bag elements in said chain comprising at most a light connection therebetween beginning in an area from a point spaced downwardly from the upper terminating ends of said seams and extending toward said bottom region of the bag elements, and a substantially stronger connection between said bags in the area adjacent the upper terminating ends of said seams, said siamese connection being operable to permit the bag elements to bow in-' wardly along the lower part'of the siamese connection accompanying filling the bags, while the strength in said upper connection is sufficient to resist inward pull along the upper part of said siamese connection accompartying said filling step.

12. The bag structure of claim 11 wherein said point in each siamese connection is relatively near said terminating ends compared to said bottom ends.

13. The bag structure of claim 11 wherein said point in each siamese connection is closely adjacent said terminating ends in comparison with relatively remote positioning of said point from said bottom ends.

14. The bag structure of claim 11 1 wherein said panels comprise tubular flexible plastic material, said upper region of the bags defining a continuous tunnel, the lower extent of which is defined by the upper terminating ends of said seams.

15. The bag elements of claim 11 wherein said bags define freely spreadable flaps adjacent said upper regions, the lower extent of said flaps being defined by the upper terminating ends of said seams.

16. The bag structure of claim 11 wherein a line of weakness exists in said upper connection to permit said bag elements to be separated therealong after filling by rupturing said upper connection along said line of weakness, said line of weakness extending upwardly beyond said terminating ends. 

1. In bag elements each generally including bottom and top ends and two sides substantially closed except at tHeir uppermost extents, respectively, and means connecting together the bags in side by side adjacent fashion to form a chain of bag elements, the improvement which comprises: certain of said means being located at least in a vicinity between the closed upper portions of the adjacent sides, respectively, of successive bag elements in said chain and terminating at a spaced predetermined distance from said bottom ends, said means having sufficient structural integrity to maintain a connection in said vicinity when subjected to a force as would be placed thereon when filling said bag elements successively, and those means located away from said vicinity being of insufficient structural integrity to maintain a connection when subjected to said force.
 2. The bag elements of claim 1 wherein said bag elements are formed from a continuous length of plastic film or sheet, and are defined by cross-seals at spaced intervals on said length of plastic, said means connecting successive bags comprising a plurality of lands having predetermined lengths and predetermined spacing from each other such that the connections made in said vicinity have a structural integrity greater than those connections located away from said vicinity.
 3. The bag elements of claim 2 wherein said lands are positioned in an area defined by said cross-seals.
 4. The bag elements of claim 2 wherein said means comprises at least a singular land located at a predetermined distance from said vicinity.
 5. The bag elements of claim 4 wherein said means define a line of weakness located within said cross-seals thereby resulting in a separation of said bags from each other after the filling thereof and said separation resulting in the development of taut lines across the upper portions of the two sides of said bags thereby providing a substantially wrinkle-free area suitable for placement of a closure seal.
 6. The bag elements of claim 5 wherein said line of weakness comprises a plurality of perforations of predetermined sizes. such that said cross-seals increase in strength when extended to a point upwardly towards said closed upper portions of said adjacent sides.
 7. A chain of bag elements each including front and rear walls and two sides substantially closed, respectively, except at a region adjacent the upper ends of said bag elements, the bags being arranged in said chain in generally side-by-side fashion; and a strip of connecting material joined along its opposite edges to said front and rear walls, respectively, to form a continuous tunnel at the upper end of each bag element, means connecting together successive bag elements in said chain at a region between the upper closed portions of their adjacent sides, respectively, said means terminating at a predetermined distance from the lower ends of said bag elements and said connecting material located generally towards the upper end of said bag elements having sufficient structural integrity to maintain a connection between said bags when subjected to the degree of force as would be placed thereon when filling the bags, and said means located generally towards the lower end of said adjacent sides having insufficient structural integrity to maintain a connection when subjected to said force thereby resulting in the separation of the lower portion of said bag elements from each other upon the filling of said bags.
 8. The bag elements of claim 7 wherein said means comprises at least one portion of connecting material thereby defining at least one slit separating said adjacent bags, and defining a line of weakness permitting the lower portions of said bag elements to separate from each other subsequent to the filling thereof.
 9. The bag elements of claim 7 wherein said strip of connecting material is adapted to be severed prior to the filling thereof, therefore to thereby provide freely speadable flaps associated with said front and rear walls, respectively.
 10. In a chain of side-by-side connected bag elements of a type formed from a continuouS length of plastic web material and including closing means for closing the sides of the bag elements from a region adjacent the bottom ends thereof to a region adjacent the top ends of the bags, the improvement of which comprises, a line of separation defined between said side closing means of adjacent bag elements in said chain, said line of separation comprising a first region located at a point spaced downwardly from the upper terminating ends of said closing means and extending toward said bottom ends, said first region providing at most only a connection between said bag elements of a degree permitting the bags to bloom apart from each other when subjected to the degree of force as would be placed thereon when filling said bag elements successively, a second region of said line of separation being located in a vicinity intermediate of said upper terminating ends and said first region, said second region providing a connection between said adjacent bag elements of a character adapted to remain substantially intact when subjected to the degree of force as would be placed thereon when filling said bag elements sucessively whereby said filling is accompanied by a tautness forming in the upper extents of said bag elements thereby providing a substantially wrinkle-free area suitable for the placement of a closure seal, said second region further providing a connection between said adjacent bag elements of a character permitting said bag elements to completely separate upon placement of said closure seal.
 11. A bag structure comprising opposed continuous panels and seams located at spaced intervals thereon to compartment said panels into a plurality of linearly connected bag elements, the bottom region of said bag elements being defined adjacent and along one longitudinally extending edge portion of said panels, means closing said bottom ends, the top end regions of said bag elements being located adjacent and along the opposite longitudinally extending edge portion of the panels, said seams extending from adjacent said bottom ends toward said opposite edge portion and terminating in spaced relationship therewith, a siamese-like connection located between adjacent bag elements in said chain comprising at most a light connection therebetween beginning in an area from a point spaced downwardly from the upper terminating ends of said seams and extending toward said bottom region of the bag elements, and a substantially stronger connection between said bags in the area adjacent the upper terminating ends of said seams, said siamese connection being operable to permit the bag elements to bow inwardly along the lower part of the siamese connection accompanying filling the bags, while the strength in said upper connection is sufficient to resist inward pull along the upper part of said siamese connection accompanying said filling step.
 12. The bag structure of claim 11 wherein said point in each siamese connection is relatively near said terminating ends compared to said bottom ends.
 13. The bag structure of claim 11 wherein said point in each siamese connection is closely adjacent said terminating ends in comparison with relatively remote positioning of said point from said bottom ends.
 14. The bag structure of claim 11 wherein said panels comprise tubular flexible plastic material, said upper region of the bags defining a continuous tunnel, the lower extent of which is defined by the upper terminating ends of said seams.
 15. The bag elements of claim 11 wherein said bags define freely spreadable flaps adjacent said upper regions, the lower extent of said flaps being defined by the upper terminating ends of said seams.
 16. The bag structure of claim 11 wherein a line of weakness exists in said upper connection to permit said bag elements to be separated therealong after filling by rupturing said upper connection along said line of weakness, said line of weakness extending upwardly beyond said terminating ends. 